Well, maybe because it would be just as futile as trying to prove or disprove god's existence
If Stephen Hawkins have said "We can assume...", then he has already stated clearly that he BELIEVES in an objective world (hence the term "WE"
)
However, a belief is not evidence.
And you still haven't offered any scientific evidence that could clarify whether or not you are just dreaming all of this, even if you BELIEVE you are not
This philosophical problem, solipsism, wont go away Hielor.
Apparently, the argument must come from within this absurd framework you have established. So be it.
You are certain, in your own mind, that you are not merely a figment of
someone else's mind. You have, as far as you can tell, free will and the ability to make your own choices concerning your own actions. So, if it is the case that everything that exists is someone's dream, it must be
your dream.
If everything around you exists only in your mind, then surely you are free to assert your will upon the "world" around you. "Use the force," if you will, to summon a pen from across the room to your hand. If the world exists entirely in your brain, why can't you? Were you able to accomplish such feats (and no other people, outside of your permission, were), then you would be able to prove to the satisfaction of the figments of your imagination that you are in fact the only consciousness in your world. Nevermind that you would have no need to perform such proof, because you could just reconstruct the figments of your imagination to be "aware" of their status as figments of your imagination, without needing to bother with any actual proving.
This is identical to the supreme-being situation -- it would be extremely easy to prove the existence of a supreme being (given the cooperation of aforementioned supreme being, of course), but it is impossible to disprove the existence of a supreme being. However, the inability to disprove something does not constitute a proof.
"Oh," say you, "but I don't have the ability to consciously manipulate the figments of my imagination."
In that case, there are two 'beings' at work here--the you which you are capable of controlling and acting upon, and the you-prime which is the imagination which is imagining both you and the world around you. Since the you has no control over the you-prime (because it has no control over the world that you-prime are dreaming), you and you-prime are, from the perspective of you, not the same. Therefore, you cannot claim that the world around you is a figment of your imagination, because it is in reality a figment of you-prime's imagination. You cannot now prove the point either way, which means that it
makes no difference. The objects and people which are not you are controlled by something other than you, regardless of what that something is.
The burden of proof, therefore, lies on you -- if you have a theory which cannot be disproven, but
can be proven, go forth and prove it; otherwise you're just being lazy in asking people to not believe differently than you.